Means for fastening bellows produced from elastomer materials, in particular pleated bellows and roller bellows, are well known. Thus, for some time so-called mutually overlapping retaining straps have been available that attain a clamping effect by tautening the two free strap ends with suitable means. However, the pleated bellows can be damaged in the region of the free strap ends, and the latter also require considerable space for installation. A number of so-called endless annularly closed clamping rings have therefore been suggested in the past. Their diameter is reduced by crimping, i.e., by radial compression by means of suitable tools, so that during the crimping process a bellows is ultimately securely held on a fastening body, for instance, a joint housing or a shaft.
To produce such endless annularly closed clamping rings, it is known to roll tape pieces trimmed from an endless tape material and butt-weld them to one another perpendicular to the center line of the ring, but this technique is very time-consuming. In contrast, instead of such welding, known from DE 40 21 746 A1 is providing on the first and second free ends of a tape segment outside and inside closure strips that are embodied complementary to one another and have undercut regions so that, when the closed connection is under tensile load, inwardly directed forces that permit a point connection of the two complementary closure strips act on the outer closure straps. An end region may be embodied, for instance, such that an essentially T-shaped head piece is embodied thereon, while the second end region complementary hereto provides a jaw-shaped fork adapted to the first end region, the two end regions linearly butting and engaging one another. A plurality of dovetail or T-shaped strips may also be provided on the ring width. Such endless annularly closed tensioning rings described in DE 40 21 746 A1 have become known as such with a so-called puzzle lock. However, it is a disadvantage of the endless tensioning ring known from DE 40 21 746 A1 that these can open occasionally, whether during transport to the consumer or user of the closed endless tensioning rings, or whether during use of the latter, for instance for retaining pleated bellows or roller bellows on outer joint housing parts or shafts. There is therefore a need for fasteners that have improved closure of the two free ends of a strip-like segment for forming an endless tensioning ring.